As a private accident reconstructionist, I don’t have the luxury of stopping traffic on a road to then take aerial images. According to FAA Part 107 guidelines I cannot fly over people or vehicles in operation. That means I cannot fly directly over a busy roadway. Is it possible to obtain a 3D map of a roadway by flying adjacent to a roadway? If so, what method (i.e. change drone height, change gimble angle, etc) might provide the best results to ensure I get enough overlap of a wide road such as a highway?
Hi Brett - Thanks for this question on the Pix4D community.
Certainly an interesting situation, and one that our public sector clients don’t encounter as they close the road down. Given your situation, your thinking is correct. We had had clients experience success in mapping a collision scene by having the drone flown adjacent to the roadway with an oblique camera angle that is looking directly at the road surface. If your camera angle (maybe 60-70 degrees, if 90 is facing straight down) and do a few flight lines off the road you should be able to achieve enough overlap.
An alternative method (less recommended but I do have clients who have been successful with this) could be to “stack” flight-lines at different altitudes. For example, fly at 100 feet, then 110 feet, then 120 feet with the oblique camera angle focused at your scene, but the drone is flying and taking photos adjacent to the roadway. We have seen this method provide enough overlap to ensure success.
Do the above help? If not - please email us directly and I am happy to get on a phone to chat.
Business Development Executive, North America
That does help, I will have to test it some more. I had previously tried the “stack” method because I had physical limitations preventing me from flying the drone further from the roadway. I did not have success with the 3D mapping but I was flying at a more oblique angle than 60-70 degrees since the roadway was very wide (around 175 feet) and I wanted to be able to capture the other side of the road without flying at a 300 ft altitude.